Di Maio's analysis of Martin's postmortem photos shows the teen's clothing was at least 2 to 4 inches away from his body.

"When someone is leaning over, their clothing tends to fall away," he said.

Zimmerman claims he shot 17-year-old Martin because he feared for his life. According to Zimmerman's story, Martin punched him, climbed on top of him, and start bashing his head into the concrete sidewalk.

If Zimmerman's defense team can convince jurors Martin was on top of him, it could bolster his claims that he shot the teenager because he was fending off an attack.